Question for Kathy-sterile larvae tank

[fin farm]

Kathy,

I was reading an old post you made in reference to sterile larvae tanks. Am I correct in saying, use 1ml bleach per gal of water? Also what brand and amount of dechlorinator do you use or brands you would not use?
thx
Larry

 

[Kathy55g]

Hi Larry,
Correct. I use sodium thiosulphate at 6g/100ml, then 1ml per gallon of water. For branded dechlorinators, you will have to figure it out. Get a set of chlorine test strips (petsmart/co)and make sure you are safe before you add anything alive.

 

[Dman]

And how often are youse doin this?

 

[Kathy55g]

Every time before a hatch, prepare tank with saltwater to match salinity of broodstock tank, add heater and heat to temperature of broodstock tank. Add ammonia alert badge, thermometer, airbubbler stone and tubing and turn on air. Add bleach at 1 ml per gallon. Leave for at least 1 hour. Then add dechlorinator until the water tests safe. Add larvae. That's what I do. I don't know if it is necessary, but it works for me.

I use the bleach/dechlorinating technique to prepare water bottles for phytoplankton culture and to reuse water change water for rotifer cultures.

 

[broncofish]

A question on the steril water. What is the purpose for the steril water? Arent you immediately adding bacteria with the larvae? I think the idea is great, I'm just curious as to why the results would be better. My first thought would be that adding any bacterium to steril water would cause that population to explode, due to there not being any competitors. But then there is also a lack of a nutrient base for that matter. Or perhaps it sets up the tank for nitrifying bacteria because fish waste would be the first food source. I just think its a cool idea, just wish I was smart enough to know why it works!

 

[Baalz]

Im lazy I just use a scrub pad and tap water.
Then just put in Broodstock tank water day of hatch.

 

[Kathy55g]

I think it effectively cleans the tank and the water of potential pathogens, and removes bacteria and nutrients. What you add with the larvae is unavoidable.

Hoff did a study with and without bleaching the tank, and showed that he got better survival on previously bleached tanks. That 's enough to convince me to do it.

 

[broncofish]

Kathy, I'd have to agree. Who cares why as long as it does!